---
url: /cube-functions/atan.md
description: Returns the arc tangent of a number.
---

# ATAN

Returns the arc tangent of a number.

```js
ATAN(input_number)
```

#### Parameters

* `input_number` - The number input.

#### Examples

```js
ATAN(0.9)
```

**Result:** `0.732815102`